Houdini 22.0 Nodes Geometry nodes

Map Points geometry node

Stores a reference on a point to another geometry’s point.

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Since 18.5

This node is used to store a mapping on a point in the first input’s geometry that references a point in the second input’s geometry. This mapping, or reference, can be an integer or string that refers to a point number or attribute on the second input’s geometry.

Parameters

Attribute

Output Attribute Name

The name of the attribute on the first input on which to store the mapping.

Reference Type

The mapping is performed on this type of data.

Point Number

The stored attribute is an integer corresponding to a point index on the second input geometry.

Attribute Value

The stored attribute is an integer or string that matches the Reference Attribute on the second input geometry.

Reference Attribute

When Reference Type is set to Attribute Value, this is the attribute that is mapped between the two input geometries.

Use MotionClip Topology

When turned on, the input geometries are interpreted as MotionClips, and points are mapped between their rest pose geometries.

Targets Group

When turned on, creates a point group of the points that are mapped to in this node. The point group is created on the second output geometry. This is useful if you want to isolate or manipulate only these points downstream.

Align Guides

Note

These parameters are used to align the skeletons in the viewport while performing the mapping operation. They do not modify the geometry in any way.

Rest Pose Attribute

The name of the Matrix4 point attribute containing the rest pose for both skeletons. If this attribute exists, it is used to display the skeleton in the viewport when performing the mapping.

Translate

When turned on, aligns the translation of the two skeletons in the viewport.

Scale to Fit

When turned on, scales the second input geometry to match the size of the first input geometry in the viewport.

Target Guide Offset

A translation offset for the second input geometry in the viewport.

Import Mappings

Imports a .json or .xml file to populate the Mappings from.

The .json file is expected to have the same syntax as that generated by the Export Mappings option.

The .xml file is expected to have the following syntax:

  • A root element called config_root.

  • A child element called match_list under which the skeleton data is stored.

  • The skeleton data should be in the form of one element, called item, per point. This element must have a value, which represents the name of the point, and a key attribute, which represents a conceptual argument that is used to match this item to another item from a different .xml file. An example point item is:

    <item key="RightUpLeg" value="thigh_r"/>

    Note

    When choosing to import a .xml file, you will be asked to first choose the file for the target skeleton, then another file for the source skeleton. Matching for .xml files works by looking up each element in both files, finding the elements that share the same key, and if the value of that element is not empty, perform the matching. This means the key must be unique per file - there cannot be 2 items with the same key, or the mapping may produce unexpected results.

Export Mappings

Exports the current Mappings to a .json file.

The exported file will contain a mappings dictionary with a key for each point in the target skeleton. Each of these keys, in turn, is a dictionary containing two distinct keys:

  • reference: Stores the mapping reference as dictated by the Reference Type parameter (ptnum when Reference Type is set to Point Number; value of the Reference Attribute parameter when Reference Type is set to Attribute Value).

  • value: Stores the mapped point on the source skeleton in the form dictated by the reference key (point number or attribute value).

Auto Map Inline Points

When turned on, attempts to find reasonable mappings in between those specified by the user.

Mappings

A list of point pairs that map points on the first input geometry to points on the second input geometry.

Inputs

Target Skeleton

The geometry on which to set the point attribute specified in Output Attribute Name.

Source Skeleton

The geometry that the Target Skeleton is mapped onto.

Outputs

Target Skeleton

The geometry on the first input with the mapping stored on the point attribute specified in Output Attribute Name.

Source Skeleton

An unmodified copy of the second input geometry.

See also

Geometry nodes